In October 2005, five autonomous vehicles (of twenty-three finalist vehicles) successfully completed the “Grand Challenge” of the United States Defense Advanced Research Projects Administration (DARPA), a competition requiring robotic vehicles to traverse a course covering more than one hundred miles. These vehicles were outfitted with robotic control systems in which a bank of computers controlled all of the operational systems of the vehicle, such as the steering, braking, transmission, and throttle, subject to autonomous decisions made by programs on board the vehicle in response to sensor input, without human intervention on the course itself.